Abstract: Methods and systems are disclosed for measuring multidimensional stress characteristics in a substrate. Generally, the methods include applying a sequence of optical pump pulses to the substrate. The optical pump pulses induce a propagating strain pulse in the substrate. Optical probe pulses are also applied. By analyzing transient optical responses caused by the propagating strain pulse, multidimensional stress components characterizing the stress in the substrate can be determined. Multidimensional stress components may also be determined at a depth of a substrate. Multidimensional stress components may also be determined at areas adjacent a through-silicon via.

Abstract: Methods and systems are disclosed for measuring multidimensional stress characteristics in a substrate. Generally, the methods include applying a sequence of optical pump pulses to the substrate. The optical pump pulses induce a propagating strain pulse in the substrate. Optical probe pulses are also applied. By analyzing transient optical responses caused by the propagating strain pulse, multidimensional stress components characterizing the stress in the substrate can be determined. Multidimensional stress components may also be determined at a depth of a substrate. Multidimensional stress components may also be determined at areas adjacent a through-silicon via.

Abstract: A pump light pulse is generating a strain pulse in a sample that includes quantum wells. A signal is measured using a probe light pulse. The probe light pulse is delayed in relation to the pump light pulse. The signal derives from a change in an optical property of the sample, which optical property responds to the generated strain pulse. One may deduce parameters of interest of the sample, including the quantum wells, from the characteristics of the signal. For discerning between various components of the stress in the quantum wells a lead pump pulse, preceding the pump light, pulse my also be used. A system for the application of such methods is also disclosed.

Abstract: A system for imposing and analyzing surface acoustic waves in a substrate to determine characteristics of the substrate is disclosed. Optical elements and arrangements for imposing and analyzing surface acoustic waves in a substrate are also disclosed. NSOM's, gratings, and nanolight elements may be used to impose surface acoustic waves in a substrate and may also be used to measure transient changes in the substrate due to the passage of surface acoustic waves therethrough.

Abstract: A pump light pulse is generating a strain pulse in a sample that includes quantum wells. A signal is measured using a probe light pulse. The probe light pulse is delayed in relation to the pump light pulse. The signal derives from a change in an optical property of the sample, which optical property responds to the generated strain pulse. One may deduce parameters of interest of the sample, including the quantum wells, from the characteristics of the signal. For discerning between various components of the stress in the quantum wells a lead pump pulse, preceding the pump light, pulse my also be used. A system for the application of such methods is also disclosed.

Abstract: An opto-acoustic transducer assembly includes a substrate; at least one layer of opto-acoustic material coupled to a surface of the substrate, where the at least one layer of opto-acoustic material generates sound waves when struck by pulses of pump light; and an acoustic lens configured to focus sound waves generated by the at least one layer of opto-acoustic material towards a sample. The acoustic lens is further configured to collect sound waves returning from the sample and to direct the returning sound waves to the at least one layer of opto-acoustic material. In one non-limiting embodiment the at least one layer of opto-acoustic material is interposed between the substrate and the acoustic lens, and the substrate is substantially transparent to light having wavelengths of interest.

Abstract: A method for characterizing a sample is described. The method includes applying a first pulse of electromagnetic radiation to the surface of the sample and thus creating a propagating strain pulse within the sample. A second pulse of second electromagnetic radiation is applied to the surface of the sample so as to intercept the propagating strain pulse. The first and second pulses are applied through a structure, such as a reflector, that is disposed over the surface of the sample at a distance predetermined to form an optical cavity; the cavity having a width related to a wavelength of the second electromagnetic radiation. The method includes detecting at least one optical property of a reflection of the second pulse from the sample. The detected optical property(ies) of the reflection are associated with a characteristic of the sample. An apparatus, computer-readable medium and structure are also described.

Abstract: A system for imposing and analyzing surface acoustic waves in a substrate to determine characteristics of the substrate is disclosed. Optical elements and arrangements for imposing and analyzing surface acoustic waves in a substrate are also disclosed. NSOM's, gratings, and nanolight elements may be used to impose surface acoustic waves in a substrate and may also be used to measure transient changes in the substrate due to the passage of surface acoustic waves therethrough.

Abstract: An optical-acoustic transducer structure includes at least one metal or semiconducting film in which a part of a pump light pulse is absorbed to generate a sound pulse; and at least one dielectric film. The thicknesses and optical properties of the at least one metal or semiconducting film and the at least one dielectric film are selected so that a returning sound pulse results in a measurable change in the optical reflectivity and/or some other optical characteristic of the transducer structure. The transducer structure includes a resonant cavity, and an output surface that is shaped so as to provide no significant focusing of generated sound waves when the sound waves are launched towards a surface of the sample.

Abstract: Disclosed is a method for characterizing a sample having a structure disposed on or within the sample, comprising the steps of applying a first pulse of light to a surface of the sample for creating a propagating strain pulse in the sample, applying a second pulse of light to the surface so that the second pulse of light interacts with the propagating strain pulse in the sample, sensing from a reflection of the second pulse a change in optical response of the sample, and relating a time of occurrence of the change in optical response to at least one dimension of the structure.

Abstract: An optical-acoustic transducer structure includes at least one metal or semiconducting film in which a part of a pump light pulse is absorbed to generate a sound pulse; and at least one dielectric film. The thicknesses and optical properties of the at least one metal or semiconducting film and the at least one dielectric film are selected so that a returning sound pulse results in a measurable change in the optical reflectivity and/or some other optical characteristic of the transducer structure. The transducer structure includes a resonant cavity, and an output surface that is shaped so as to provide no significant focusing of generated sound waves when the sound waves are launched towards a surface of the sample.

Abstract: Disclosed is a method for characterizing a sample having a structure disposed on or within the sample, comprising the steps of applying a first pulse of light to a surface of the sample for creating a propagating strain pulse in the sample, applying a second pulse of light to the surface so that the second pulse of light interacts with the propagating strain pulse in the sample, sensing from a reflection of the second pulse a change in optical response of the sample, and relating a time of occurrence of the change in optical response to at least one dimension of the structure.

Abstract: Disclosed is a method for characterizing a sample having a structure disposed on or within the sample, comprising the steps of applying a first pulse of light to a surface of the sample for creating a propagating strain pulse in the sample, applying a second pulse of light to the surface so that the second pulse of light interacts with the propagating strain pulse in the sample, sensing from a reflection of the second pulse a change in optical response of the sample, and relating a time of occurrence of the change in optical response to at least one dimension of the structure.

Abstract: A method for characterizing a sample is described. The method includes applying a first pulse of electromagnetic radiation to the surface of the sample and thus creating a propagating strain pulse within the sample. A second pulse of second electromagnetic radiation is applied to the surface of the sample so as to intercept the propagating strain pulse. The first and second pulses are applied through a structure, such as a reflector, that is disposed over the surface of the sample at a distance predetermined to form an optical cavity; the cavity having a width related to a wavelength of the second electromagnetic radiation. The method includes detecting at least one optical property of a reflection of the second pulse from the sample. The detected optical property(ies) of the reflection are associated with a characteristic of the sample. An apparatus, computer-readable medium and structure are also described.

Abstract: An opto-acoustic transducer assembly includes a substrate; at least one layer of opto-acoustic material coupled to a surface of the substrate, where the at least one layer of opto-acoustic material generates sound waves when struck by pulses of pump light; and an acoustic lens configured to focus sound waves generated by the at least one layer of opto-acoustic material towards a sample. The acoustic lens is further configured to collect sound waves returning from the sample and to direct the returning sound waves to the at least one layer of opto-acoustic material. The at least one layer of opto-acoustic material is responsive to the returning sound waves for having at least one optical property thereof changed, where the change is detectable from a change in a characteristic of reflected pulses of probe light that are time delayed with respect to the pulses of pump light.

Abstract: Disclosed is a method for characterizing a sample having a structure disposed on or within the sample, comprising the steps of applying a first pulse of light to a surface of the sample for creating a propagating strain pulse in the sample, applying a second pulse of light to the surface so that the second pulse of light interacts with the propagating strain pulse in the sample, sensing from a reflection of the second pulse a change in optical response of the sample, and relating a time of occurrence of the change in optical response to at least one dimension of the structure.

Abstract: Disclosed is a method for characterizing a sample having a structure disposed on or within the sample, comprising the steps of applying a first pulse of light to a surface of the sample for creating a propagating strain pulse in the sample, applying a second pulse of light to the surface so that the second pulse of light interacts with the propagating strain pulse in the sample, sensing from a reflection of the second pulse a change in optical response of the sample, and relating a time of occurrence of the change in optical response to at least one dimension of the structure.

Abstract: Disclosed is a method for characterizing a sample having a structure disposed on or within the sample, comprising the steps of applying a first pulse of light to a surface of the sample for creating a propagating strain pulse in the sample, applying a second pulse of light to the surface so that the second pulse of light interacts with the propagating strain pulse in the sample, sensing from a reflection of the second pulse a change in optical response of the sample, and relating a time of occurrence of the change in optical response to at least one dimension of the structure.

Abstract: A method for the determination of grain orientation in a film sample is provided comprising the steps of measuring a first transient optical response of the film and determining the contribution to the transient optical response arising from a change in the energy distribution of the electrons in the sample, determining the contribution to the transient optical response arising from a propagating strain pulse within the sample, and determining the contribution to the transient optical response arising from a change in sample temperature of the sample. The grain orientation of the sample may be determined using the contributions to the transient optical response arising from the change in the energy distribution of the electrons, the propagating strain pulse, and the change in sample temperature. Additionally, a method for determination of the thickness of a film sample is provided. The grain orientation of the sample is first determined.

Abstract: A method and a system are disclosed for determining at least one characteristic of a sample that contains a substrate and at least one film disposed on or over a surface of the substrate. The method includes a first step of placing a mask over a free surface of the at least one film, where the mask has a top surface and a bottom surface that is placed adjacent to the free surface of the film. The bottom surface of the mask has formed therein or thereon a plurality of features for forming at least one grating. A next step directs optical pump pulses through the mask to the free surface of the film, where individual ones of the pump pulses are followed by at least one optical probe pulse. The pump pulses are spatially distributed by the grating for launching a plurality of spatially distributed, time varying strain pulses within the film, which cause a detectable change in optical constants of the film.